There has been a growing need for automated systems that use cameras to analyze a surrounding environment. In many applications, it is desirable that a system can dynamically change the viewing direction of the camera, and/or capture multiple moving objects with high resolution. The conventional solution is to use mechanical pan-tilt-zoom cameras, which are cameras that change their viewing direction using motors that physically rotate the cameras. Variable zoom can be achieved by mechanically moving the lenses.
The conventional solution, however, has several limitations. First, due to mechanical constraints, it is difficult to achieve a prompt and accurate change of the viewing direction or of the zoom factor from one video frame to the next. Second, the continuous changes of imaging properties introduce motion blur into the captured video image. Third, the motors tend to wear after long or repetitive usage, which poses a particularly significant problem for systems whose maintenance is expensive or for systems deployed in inaccessible locations. Finally, cameras today are restricted to acquiring images with a continuous field of view. Therefore, for a camera to simultaneously capture multiple objects that are of a distance from each other, the camera must maintain a wide field of view and, hence, acquire images of the objects with lower resolution. To overcome this limitation, conventional systems use multiple cameras, which results in complex designs and higher prices.
Therefore, an imaging device that can acquire images with disjointed fields of view, and can dynamically change its viewing direction, zoom factor, and/or other imaging properties without physically moving the components of the device is highly desirable. The present invention is directed to these and other important objectives.